Apply a Fuzzy Method to Perform Objective Allocation for Buildings Cost in Value Engineering Job Plan Process

Because of its benefits, value engineering (VE) has been applied in the public sector of construction industry through systematic VE job plan workshop. However, unsatisfactory VE workshop have often been reported used to the deficient in the traditional VE job plan, which has hampered the VE application for private projects. The function analysis phase plays a key role in delivering VE workshop outcomes, while how to efficiently and objectively allocate building cost to each function has long been a problem. Current study applied a fuzzy-based method to improve the traditional function cost allocation in terms of objectivity and efficiency. Triangular fuzzy numbers (TFNs), as one of fuzzy methods, is applied to transfer the VE participants’ linguistic and vague evaluation of the function performance of the building elements into numerical values. A real case study was carried out to examine the proposed method. In the case study, a group of VE participants was able to establish a Function Analysis System Techniques (FAST) diagram for the case building, and give their linguistic evaluation in different degree about the function performance of specific building elements. The linguistic evaluation was then transferred to numerical value by TFNs algorithms in order to understand the function performance of building elements, which laid the ground for allocating cost of building elements to functions. The findings indicated that the function cost allocation through the TFNs are generally reasonable and reliable, which could be applied to benefit other VE projects. Current study was able to contribute to improve current VE practices by offering the way to objectively and efficiently allocate function cost.